According to the speeding up and energy saving of printers and duplicators in recent years, a toner meeting these requirements is getting to be necessary.
PTL 1 describes, as a means for solving a problem of achieving both the wrapping and low-temperature offset occurring in use of a high-speed machine and the development stability in long-term use, a toner containing at least a binder resin, a colorant, a release agent, and a crystalline polyester, in which the release agent contains a hexafunctional or higher functional alkylcarboxylate ester as a major component, and the toner contains insoluble in tetrahydrofuran (THF) component derived from the binder resin formed through Soxhlet extraction of the toner with THF of 5.0% by mass or more and 50.0% by mass or less.
PTL 2 describes, as a means for solving a problem of preventing the low-temperature offset and achieving both the low-temperature fusing property and the heat resistant storage stability, a toner containing toner particles having a core-shell structure containing a core containing a binder resin A, a colorant, and wax, having formed thereon a shell phase containing a resin B, in which the binder resin A and the binder resin B satisfy the particular characteristics in flow characteristic measurement.
PTL 1: JP 2010-145550 A
PTL 2: JP 2014-32232 A